The present invention relates generally to electric shavers and, more particularly, to a biasing mechanism for an electric shaver with a pivoting head.
Oscillating electric shavers conventionally include a handle and a head mounted on the handle, and the head carries at least one set of inner and outer cutter blades. Each outer cutter blade, which is typically elongated in shape, is supported by a frame of the shaver head and typically defines the skin contacting surface of the shaver. Openings formed in the outer cutter allow hair to protrude through the outer cutter below an inner surface thereof as the shaver is moved over a user's skin. Each inner cutter blade is housed in the shaver head below a corresponding outer cutter and in sliding engagement with the inner surface of the outer cutter. The inner cutter blade is driven by an electric motor, typically housed within the handle, whereby oscillation of the inner cutter acts to cut hairs protruding through the outer cutter.
In some oscillating shaver constructions, the head is pivotably mounted on the handle by a pair of opposed support arms that extend from the top of the handle. Specifically, each support arm extends from the handle to a distal end, and the head is mounted between the support arms such that the pivot axis of the head is located near the distal ends of the support arms. In this manner, the head has a first orientation (e.g., an orientation at which the support arms are substantially centered on the sides of the head). The head is pivotable from the first orientation toward at least one of the front or back of the shaver into a second orientation (e.g., an orientation at which the support arms are not substantially centered on the sides of the head). When the head is not maintained in the second orientation (e.g., when the head is not held against a contour of the skin), the head may be biased back to the first orientation. With this configuration, the shaver head can freely pivot about contours of the skin during shaving, thereby enabling the user to better maintain the outer cutter in contact with the skin. Additionally, after shaving, the head can be biased back toward an orientation that facilitates preventing the shaver head from interfering with an extendable trimmer that may be mounted on the front or back of the handle.
In such a construction, however, the biasing mechanism experiences significant stresses (e.g., repeated tensioning and friction) associated with the repeated pivoting of the head from one orientation to another, which can cause the biasing mechanism to fatigue. There is a need, therefore, for an electric shaver with a biasing mechanism that is configured to provide effective biasing of the shaver head while being able to better withstand repeated stresses associated therewith.